Filtered Clients Setup - libbitcoin/libbitcoin-server GitHub Wiki
Access to a server's endpoints can be limited to a list of IP addresses, as follows. This configuration limits both secure and public endpoints.
The client-server endpoints are currently limited to IPv4 addressing.
[server]
client_address = 127.0.0.1
client_address = 192.168.1.42
client_address = 192.168.1.43
client_address = 192.168.1.44
Blocked addresses can be incorporated with client addresses. In the case of conflict client_address wins over blacklist addresses regardless of ordering.
[server]
client_address = 127.0.0.1
client_address = 192.168.1.42
client_address = 192.168.1.43
client_address = 192.168.1.44
blacklist = 10.10.10.42
blacklist = 10.10.10.43
Given that an IP address can be spoofed this form of access control is weak, but may be sufficient in certain scenarios. For strong access control use restricted clients.